/* 全局样式 */
body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  margin: 0;
  padding: 0;
  color: #333;
  background-color: #f9f9f9;
}

/* 加载屏幕 */
.loading-screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(255, 255, 255, 0.9);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 999;
}

.spinner {
  border: 4px solid rgba(0, 0, 0, 0.1);
  border-left-color: #007BFF;
  border-radius: 50%;
  width: 50px;
  height: 50px;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* 顶部导航栏 */
.navbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 30px;
  background-color: #fff;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 100;
  transition: all 0.3s ease;
}

.navbar.scrolled {
  background-color: #f8f8f8;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.15);
  transform: translateY(-2px);
}

.logo {
  font-size: 28px;
  font-weight: bold;
  color: #007BFF;
}

.tabs a {
  margin-right: 25px;
  text-decoration: none;
  color: #333;
  font-size: 16px;
  transition: color 0.3s ease;
}

.tabs a:hover {
  color: #007BFF;
}

.buttons button {
  margin-left: 15px;
  padding: 10px 20px;
  border: none;
  background-color: #007BFF;
  color: #fff;
  cursor: pointer;
  border-radius: 5px;
  font-size: 16px;
  transition: background-color 0.3s ease;
}

.buttons button:hover {
  background-color: #0056b3;
}

/* 侧边栏 */
.sidebar {
  width: 280px;
  padding: 30px;
  border-right: 1px solid #eee;
  position: sticky;
  top: 70px;
  height: calc(100vh - 70px);
  overflow-y: auto;
}

.sidebar-card {
  margin-bottom: 30px;
}

.sidebar-card img {
  width: 100px;
  height: 100px;
  border-radius: 50%;
  margin-bottom: 10px;
}

.sidebar-card p {
  margin: 5px 0;
}

/* 帖子列表 */
.post-item {
  display: flex;
  margin-bottom: 30px;
  padding: 30px;
  border: 1px solid #eee;
  border-radius: 10px;
  background-color: #fff;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.post-item:nth-child(odd) {
  background-color: #fcfcfc;
}

.post-item:nth-child(even) {
  background-color: #fafafa;
}

.post-item:hover {
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
  transform: translateY(-5px);
  background-color: #eef6ff;
}

.post-cover {
  margin-right: 30px;
  position: relative;
  overflow: hidden;
  min-width: 250px;
}

.post-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: 10px;
  transition: transform 0.3s ease;
}

.post-cover img:hover {
  transform: scale(1.1) rotate(2deg);
  filter: brightness(0.9);
}

.post-cover::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.2);
  opacity: 0;
  transition: opacity 0.3s ease;
  border-radius: 10px;
}

.post-cover:hover::before {
  opacity: 1;
}

.post-info {
  flex: 1;
}

.post-info p {
  margin: 8px 0;
  transition: color 0.3s ease;
}

.post-info p:first-child {
  font-size: 22px;
  font-weight: bold;
  color: #007BFF;
}

.post-info p:nth-child(2) {
  color: #777;
}

.post-info p:nth-child(3) {
  color: #007BFF;
}

.post-item:hover .post-info p {
  color: #000;
}

.post-read-more {
  position: absolute;
  bottom: 20px;
  right: 20px;
  background-color: #007BFF;
  color: white;
  padding: 8px 15px;
  border-radius: 5px;
  opacity: 0;
  transition: opacity 0.3s ease;
  text-decoration: none;
  font-size: 14px;
  z-index: 1;
}

.post-item:hover .post-read-more {
  opacity: 1;
}

/* 底部 Footer */
.footer {
  text-align: center;
  padding: 20px;
  background-color: #f8f8f8;
  border-top: 1px solid #eee;
}